Major League Baseball chief operating officer Rob Manfred is on the witness list for Alex Rodriguez's appeal of his 211-game suspension in the Biogenesis probe, a person familiar with the process said Wednesday.

Manfred is the league's representative on the three-person panel overseeing the arbitration process, but he has no say in the final decision made by chief arbitrator Fredric Horowitz, who can uphold the suspension, overturn it or reduce it. David Prouty of the Major League Baseball Players Association is the third member of the panel.

According to the article,

Rodriguez's attorneys are likely to challenge Manfred's appearance, though a source said Manfred has been on the witness list for some time. Manfred's testimony is considered key in MLB's contention that Biogenesis founder Anthony Bosch was not paid for his testimony. Manfred, who is second to commissioner Bud Selig, led MLB's investigation into Biogenesis.

The article ultimately concludes that

While baseball arbitration is considered an informal process, legal experts view the potential testimony by Manfred as unusual. "Rules of evidence would prohibit a hearing officer from testifying at his own hearing," New Jersey attorney John Furlong said. "If he does testify, it speaks volumes to the lack of adherence to a semblance of evidence protocol." Manhattan attorney Stephan Kallas added, "I would think down the road if Alex Rodriguez decides to bring the arbitration decision to a federal judge that it's possible that a judge would frown upon this method of arbitration."